Techniques For Reducing Human Exposure To Wireless Energy In Wireless Power Delivery Environments

ABSTRACT

Embodiments of the present disclosure describe techniques for reducing human exposure to wireless energy in wireless power delivery environments. In some embodiments, a wireless power reception apparatus configured to receive wireless power from a wireless charging system in a wireless power delivery environment is disclosed. The wireless power reception apparatus includes a control system and an antenna array. In some embodiments, the control system is configured to dynamically adjust transmission and reception radiation patterns of the antenna array to reduce human exposure to wireless radio frequency (RF) energy.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/243,611 titled “TECHNIQUES FOR REDUCING HUMAN EXPOSURE TO WIRELESSENERGY IN WIRELESS POWER DELIVERY ENVIRONMENTS” filed on Jan. 9, 2019,now allowed; which is a continuation of U.S. patent application Ser. No.15/881,983 titled “TECHNIQUES FOR REDUCING HUMAN EXPOSURE TO WIRELESSENERGY IN WIRELESS POWER DELIVERY ENVIRONMENTS” filed on Jan. 29, 2018,and issued as U.S. Pat. No. 10,181,730 on Jan. 15, 2019; which is acontinuation of U.S. patent application Ser. No. 14/988,010 titled“TECHNIQUES FOR REDUCING HUMAN EXPOSURE TO WIRELESS ENERGY IN WIRELESSPOWER DELIVERY ENVIRONMENTS” filed on Jan. 5, 2016, and issued on Jan.30, 2018, as U.S. Pat. No. 9,882,398; which claims priority to andbenefit from U.S. Provisional Patent Application No. 62/100,007 titled“TECHNIQUES FOR REDUCING SPECIAL ABSORPTION RATE LEVELS FOR WIRELESSLYPOWERED DEVICES” filed on Jan. 5, 2015, all of which are expresslyincorporated by reference herein.

TECHNICAL FIELD

The technology described herein relates generally to the field ofwireless power delivery and, more particularly, to techniques forreducing human exposure to wireless energy in wireless power deliveryenvironments.

BACKGROUND

Delivering power wirelessly, e.g., via radio frequency (RF), toelectronic devices within close proximity to the human flesh can raisesafety concerns due to the potential for absorption of the RF energy bythe human flesh. The Federal Communications Commission (FCC) currentlylimits the exposure or Special Absorption Rate (SAR) to 1.6 mW/cm³ forfrequencies above 1 GHz. Staying below this limit is achievable by mostwireless devices that primarily transmit and receive datacommunications. However, this limit can be easily reached or exceeded inenvironments wherein wireless power is delivered.

Accordingly, a need exists for technology that overcomes the problemdemonstrated above, as well as one that provides additional benefits.The examples provided herein of some prior or related systems and theirassociated limitations are intended to be illustrative and notexclusive. Other limitations of existing or prior systems will becomeapparent to those of skill in the art upon reading the followingDetailed Description.

OVERVIEW

Provided herein are systems, methods, and software that facilitatevarious reduction of human exposure to wireless energy in wireless powerdelivery environments. In some embodiments, a wireless power receptionapparatus is disclosed having multiple antennas and a control system.The control system is configured to dynamically adjust a cumulativeradiation pattern of the multiple antennas to reduce radio frequency(RF) exposure to a user of an electronic device in which the wirelesspower reception apparatus is embedded. The wireless power receptionapparatus is further configured to receive wireless power from awireless power delivery system in a wireless power delivery environmentand to provide the power to the electronic device.

In some embodiments, the wireless power reception apparatus dynamicallyadjusts the cumulative radiation pattern of the multiple antennas bycontrolling a direction and intensity of a beacon signal transmitted bythe multiple antennas.

In some embodiments, the wireless power reception apparatus dynamicallyadjusts the cumulative radiation pattern of the multiple antennas bycontrolling an angle of incidence of the wireless power received fromthe wireless power delivery system.

In some embodiments, the multiple antennas each have correspondingradiation patterns that are controlled over amplitude and phase by thecontrol system. In some embodiments, the radiation patterns of themultiple antennas collectively comprise the cumulative radiationpattern.

In some embodiments, the control system is further configured to detectan orientation of the multiple antennas relative to the user of theelectronic device and to dynamically adjust the cumulative radiationpattern of the multiple antennas based on the orientation of themultiple antennas relative to the user of the electronic device.

In some embodiments, the control system is further configured to detecta full or partial blockage of one or more of the multiple antennas andto dynamically adjust the cumulative radiation pattern of the multipleantennas based on the full or partial blockage of the one or more of themultiple antennas.

In some embodiments, the control system is preconfigured with a set offixed cumulative radiation patterns, and the control system isconfigured to cycle through the set of fixed cumulative radiationpatterns to identify an optimal antenna configuration for reducing RFexposure to the user of an electronic device.

In some embodiments, the control system is configured to dynamicallyadjust the cumulative radiation pattern in a direction away from theuser of the electronic device.

In some embodiments, the multiple antennas are configured to have thesame resonance frequency.

In some embodiments, an electronic device is disclosed having electroniccomponents including one or more processors, multiple antennas disposedon or within the electronic device, and a computer-readable storagemedium. The computer-readable storage medium has instructions storedthereon which, when executed by the one or more processors, direct theelectronic device to dynamically adjust a cumulative radiation patternof the multiple antennas to reduce radio frequency (RF) exposure to auser of an electronic device in which the wireless power receptionapparatus is embedded. The multiple antennas each have a correspondingradiation pattern that is controlled over amplitude and phase, theradiation patterns collectively comprising the cumulative radiationpattern. The wireless power reception apparatus is configured to receivewireless power from a wireless power delivery system in a wireless powerdelivery environment and to provide the power to the electronic device.

In some embodiments, the electronic device dynamically adjusts thecumulative radiation pattern of the multiple antennas by controlling adirection and intensity of a beacon signal transmitted by the multipleantennas or directing an angle of incidence of the wireless powerreceived from the wireless power delivery system.

In some embodiments, the instructions, when executed by the one or moreprocessors, further direct the electronic device to detect anorientation of the multiple antennas relative to the user of theelectronic device and dynamically adjust the cumulative radiationpattern based on the orientation of the multiple antennas relative tothe user of the electronic device.

In some embodiments, the instructions, when executed by the one or moreprocessors, further direct the electronic device to detect a full orpartial blockage of one or more of the multiple antennas by the user ofthe electronic device and dynamically adjust the cumulative radiationpattern based on the full or partial blockage.

In some embodiments, the instructions, when executed by the one or moreprocessors, further direct the electronic device to cycle through a setof fixed cumulative radiation patterns to identify an optimal antennaconfiguration for reducing RF exposure to the user of an electronicdevice. The control system is preconfigured with the set of fixedcumulative radiation patterns.

In some embodiments, the instructions, when executed by the one or moreprocessors, direct the electronic device to dynamically adjust thecumulative radiation pattern in a direction away from the user of theelectronic device.

In some embodiments, a method of operating a wireless power receptionapparatus to reduce radio frequency (RF) exposure to a user of anelectronic device in which the wireless power reception apparatus isembedded is disclosed. The method includes detecting an orientation ofan antenna array of the wireless power reception apparatus relative to auser of the electronic device and adjusting a cumulative radiationpattern of the antenna array to reduce the RF exposure to the user of anelectronic device. Each antenna of the antenna array has a correspondingradiation pattern that is controlled over amplitude and phase, theradiation patterns collectively comprise the cumulative radiationpattern. The wireless power reception apparatus is configured to receivewireless power from a wireless power delivery system in a wireless powerdelivery environment and to provide the power to the electronic device.

In some embodiments, the method further includes detecting theorientation of the antenna array of the wireless power receptionapparatus relative to the user of the electronic device comprisesidentifying a full or partial blockage of one or more antennas of theantenna array by the user of the electronic device.

This Overview is provided to introduce a selection of concepts in asimplified form that are further described below in the TechnicalDisclosure. It may be understood that this Overview is not intended toidentify key features or essential features of the claimed subjectmatter, nor is it intended to be used to limit the scope of the claimedsubject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the present invention are illustrated by wayof example and not limitation in the figures of the accompanyingdrawings, in which like references indicate similar elements.

FIG. 1 depicts a diagram illustrating example components of a wirelesspower delivery environment in accordance with some embodiments.

FIG. 2 depicts a sequence diagram illustrating example operationsbetween a wireless charger and a wireless receiver device in accordancewith some embodiments.

FIG. 3 depicts a block diagram illustrating example components of awireless power transmitter (charger or wireless power delivery system)in accordance with some embodiments.

FIG. 4 depicts a block diagram illustrating example components of awireless power receiver (client) in accordance with some embodiments.

FIG. 5 depicts a diagram illustrating example components of a wirelesspower delivery environment 500, according to some embodiments.

FIG. 6 depicts a diagram illustrating example components of a wirelesspower reception apparatus 600, according to some embodiments.

FIGS. 7A-7C depict diagrams illustrating various example antennaradiation patterns of a configurable antenna array, according to someembodiments.

FIG. 8 illustrates an example of a more detailed antenna array 805 whichincludes nine antennas 806 a-i each having a corresponding antennaradiation pattern that can be controlled over amplitude and phase.

FIG. 9 depicts a diagram illustrating an example multi-path wirelesspower delivery environment 900, according to some embodiments.

FIG. 10 depicts a flow diagram illustrating an example process fordynamically adjusting radiation transmission and reception patternsbased on monitored transmitted signals, e.g., beacon signals.

FIG. 11 depicts a flow diagram illustrating an example process 1000 fordynamically reconfiguring antenna array configurations, according tosome embodiments.

FIGS. 12A-12F depict various diagrams illustrating additional techniquesfor reducing human exposure to wireless energy, e.g., RF energy, inwireless power delivery environments utilizing glass front antennas.

FIG. 13 depicts a block diagram illustrating example components of arepresentative mobile device or tablet computer with a wireless powerreceiver or client in the form of a mobile (or smart) phone or tabletcomputer device, according to some embodiments.

FIG. 14 depicts a diagrammatic representation of a machine, in theexample form, of a computer system within which a set of instructions,for causing the machine to perform any one or more of the methodologiesdiscussed herein, may be executed.

DETAILED DESCRIPTION

The following description and drawings are illustrative and are not tobe construed as limiting. Numerous specific details are described toprovide a thorough understanding of the disclosure. However, in certaininstances, well-known or conventional details are not described in orderto avoid obscuring the description. References to one or an embodimentin the present disclosure can be, but not necessarily are, references tothe same embodiment; and, such references mean at least one of theembodiments.

Reference in this specification to “one embodiment” or “an embodiment”means that a particular feature, structure, or characteristic describedin connection with the embodiment is included in at least one embodimentof the disclosure. The appearances of the phrase “in one embodiment” invarious places in the specification are not necessarily all referring tothe same embodiment, nor are separate or alternative embodimentsmutually exclusive of other embodiments. Moreover, various features aredescribed which may be exhibited by some embodiments and not by others.Similarly, various requirements are described which may be requirementsfor some embodiments but no other embodiments.

The terms used in this specification generally have their ordinarymeanings in the art, within the context of the disclosure, and in thespecific context where each term is used. Certain terms that are used todescribe the disclosure are discussed below, or elsewhere in thespecification, to provide additional guidance to the practitionerregarding the description of the disclosure. For convenience, certainterms may be highlighted, for example using italics and/or quotationmarks. The use of highlighting has no influence on the scope and meaningof a term; the scope and meaning of a term is the same, in the samecontext, whether or not it is highlighted. It will be appreciated thatsame thing can be said in more than one way.

Consequently, alternative language and synonyms may be used for any oneor more of the terms discussed herein, nor is any special significanceto be placed upon whether or not a term is elaborated or discussedherein. Synonyms for certain terms are provided. A recital of one ormore synonyms does not exclude the use of other synonyms. The use ofexamples anywhere in this specification, including examples of any termsdiscussed herein, is illustrative only, and is not intended to furtherlimit the scope and meaning of the disclosure or of any exemplifiedterm. Likewise, the disclosure is not limited to various embodimentsgiven in this specification.

Without intent to further limit the scope of the disclosure, examples ofinstruments, apparatus, methods and their related results according tothe embodiments of the present disclosure are given below. Note thattitles or subtitles may be used in the examples for convenience of areader, which in no way should limit the scope of the disclosure. Unlessotherwise defined, all technical and scientific terms used herein havethe same meaning as commonly understood by one of ordinary skill in theart to which this disclosure pertains. In the case of conflict, thepresent document, including definitions, will control.

Embodiments of the present disclosure describe techniques for reducinghuman exposure to wireless energy in wireless power deliveryenvironments.

I. Wireless Power Delivery System Overview/Architecture

FIG. 1 is a diagram illustrating example components of a wireless powerdelivery environment 100. More specifically, FIG. 1 illustrates anexample wireless power delivery environment 100 in which wireless powerand/or data can be delivered from one or more wireless chargers 101 towireless devices 102.1-102.n having one or more power receiver clients103.1-103.n (also referred to herein as “wireless power receivers” or“wireless power clients”). The wireless power receivers are configuredto receive and/or otherwise harvest the wireless power transmitted bythe one or more wireless chargers 101 and provide the received wirelesspower to the corresponding wireless device 102.1-102.n.

As shown in the example of FIG. 1, the wireless devices 102.1-102.n aremobile phone devices 102.2 and 102.n, respectively, and a wireless gamecontroller 102.1, although the wireless devices 102.1-102.n can be any(smart or dumb, mobile or static) device or system that needs power andis capable of receiving wireless power via one or more integrated powerreceiver clients 103.1-103.n. As discussed herein, the one or moreintegrated power receiver clients or “wireless power receivers” receiveand process power from one or more transmitters/chargers 101.a-101.n andprovide the power to the wireless devices 102.1-102.n for operationthereof.

Each charger 101 (also referred to herein as a “transmitter”, “array ofantennas” or “antenna array system”) can include multiple antennas 104,e.g., an antenna array including hundreds or thousands of antennas,which are capable of delivering wireless power to wireless devices 102.In some embodiments, the antennas are adaptively-phased radio frequencyantennas. The charger 101 is capable of determining the appropriatephases to deliver a coherent power transmission signal to the powerreceiver clients 103. The array is configured to emit a signal (e.g.,continuous wave or pulsed power transmission signal) from multipleantennas at a specific phase relative to each other. It is appreciatedthat use of the term “array” does not necessarily limit the antennaarray to any specific array structure. That is, the antenna array doesnot need to be structured in a specific “array” form or geometry.Furthermore, as used herein the term “array” or “array system” may beused include related and peripheral circuitry for signal generation,reception and transmission, such as radios, digital logic and modems. Insome embodiments, the charger 101 can have an embedded Wi-Fi hub.

The wireless devices 102 can include one or more receive power clients103. As illustrated in the example of FIG. 1, power delivery antennas104 a and data communication antennas 104 b are shown. The powerdelivery antennas 104 a are configured to provide delivery of wirelessradio frequency power in the wireless power delivery environment. Thedata communication antennas are configured to send data communicationsto and receive data communications from the power receiver clients103.1-103 and/or the wireless devices 102.1-102.n. In some embodiments,the data communication antennas can communicate via Bluetooth, Wi-Fi,ZigBee, etc.

Each power receiver client 103.1-103.n includes one or more antennas(not shown) for receiving signals from the chargers 101. Likewise, eachcharger 101.a-101.n includes an antenna array having one or moreantennas and/or sets of antennas capable of emitting continuous wavesignals at specific phases relative to each other. As discussed above,each array is capable of determining the appropriate phases fordelivering coherent signals to the power receiver clients 102.1-102.n.For example, coherent signals can be determined by computing the complexconjugate of a received beacon signal at each antenna of the array suchthat the coherent signal is properly phased for the particular powerreceiver client that transmitted the beacon signal.

Although not illustrated, each component of the environment, e.g.,wireless power receiver, charger, etc., can include control andsynchronization mechanisms, e.g., a data communication synchronizationmodule. The chargers 101.a-101.n can be connected to a power source suchas, for example, a power outlet or source connecting the chargers to astandard or primary alternating current (AC) power supply in a building.Alternatively or additionally, one or more of the chargers 101.a-101.ncan be powered by a battery or via other mechanisms.

In some embodiments, the power receiver clients 102.1-102.n and/or thechargers 101.a-101.n utilize reflective objects 106 such as, forexample, walls or other RF reflective obstructions within range totransmit beacon signals and/or receive wireless power and/or data withinthe wireless power delivery environment. The reflective objects 106 canbe utilized for multi-directional signal communication regardless ofwhether a blocking object is in the line of sight between the chargerand the power receiver client.

As described herein, each wireless device 102.1-102.n can be any systemand/or device, and/or any combination of devices/systems that canestablish a connection with another device, a server and/or othersystems within the example environment 100. In some embodiments, thewireless devices 102.1-102.n include displays or other outputfunctionalities to present data to a user and/or input functionalitiesto receive data from the user. By way of example, a wireless device 102can be, but is not limited to, a video game controller, a serverdesktop, a desktop computer, a computer cluster, a mobile computingdevice such as a notebook, a laptop computer, a handheld computer, amobile phone, a smart phone, a PDA, a Blackberry device, a Treo, and/oran iPhone, etc. The wireless device 102 can also be any wearable devicesuch as watches, necklaces, rings or even devices embedded on or withinthe customer. Other examples of a wireless device 102 include, but arenot limited to, safety sensors (e.g., fire or carbon monoxide), electrictoothbrushes, electronic door lock/handles, electric light switchcontroller, electric shavers, etc.

Although not illustrated in the example of FIG. 1, the charger 101 andthe power receiver clients 103.1-103.n can each include a datacommunication module for communication via a data channel. Alternativelyor additionally, the power receiver clients 103.1-103.n can direct thewireless devices 102.1-102.n to communicate with the charger viaexisting data communications modules. Additionally, in some embodimentsthe beacon signal, which is primarily referred to herein as a continuouswaveform, can alternatively or additionally take the form of a modulatedsignal.

FIG. 2 is a sequence diagram 200 illustrating example operations betweena wireless charger 101 and a power receiver client 103, according to anembodiment. Initially, communication is established between the charger101 and the power receiver client 103. The charger 101 subsequentlysends beacon schedule information and a transmission code to the powerreceiver client 103 to facilitate encoding of the beacon signal by thepower receiver client 103 for subsequent isolated wireless powerdelivery by the charger. The charger 101 can also send powertransmission scheduling information so that the power receiver client103 knows when to expect wireless power from the charger. As discussedherein, the power receiver client 103 generates an encoded beacon signalusing the transmission code and broadcasts the encoded beacon during abeacon transmission assignment indicated by the beacon scheduleinformation, e.g., BBS cycle.

As shown, the charger 101 receives the beacon from the power receiverclient 103 and decodes the encoded beacon signal using the transmissioncode provided to the client 103 to ensure that the client 103 is anauthorized or selected client. The charger 101 also detects the phase(or direction) at which the beacon signal is received and, once thecharger determines that the client is authorized, delivers wirelesspower and/or data to the power receiver client 103 based the phase (ordirection) of the received beacon.

In some embodiments, the charger 101 determines the complex conjugate ofthe phase and uses the complex conjugate to deliver and/or otherwisedirect or return wireless power to the power receiver client 103 via thesame multiple paths over which the beacon signal is received by thecharger 101. Advantageously, this technique results in isolated wirelesspower delivery to the power receiver client 103. As discussed herein,the precise location where the multiple paths of the isolated powerdelivery converge at the power receiver client 103, i.e., where thewireless energy is focused by the charger over the multiple paths, canbe referred to herein as an RF energy pocket or a power ball.

As discussed below, in some embodiments, the precise location of the RFenergy pocket or power ball and/or the angle of incidence of the RFenergy received at the RF energy pocket or power ball can be controlledvia modification to the amplitude and/or phase of an antenna array ofthe power receiver client 103 or the wireless device 102.Advantageously, the modification techniques reduce and/or otherwiseavoid absorption of wireless energy, e.g., RF energy, by human flesh ofuser that is proximate to the wireless device.

In some embodiments, the charger 101 includes many antennas; one or moreof which are used to deliver power to the power receiver client 103. Thecharger 101 can detect phases at which the beacon signals are receivedat each antenna. The large number of antennas may result in differentcoded beacon signals being received at each antenna of the charger 101.The charger may then determine the complex conjugate of the beaconsignals received at each antenna. Using the complex conjugates, one ormore antenna may emit a signal that takes into account the effects ofthe large number of antennas in the charger 101. In other words, thecharger 101 emits a signal from one or more antennas in such a way as tocreate an aggregate signal from the one or more of the antennas thatapproximately recreates the waveform of the beacon in the oppositedirection.

As discussed herein, wireless power can be delivered in power cyclesdefined by power schedule information. A more detailed example of thesignaling required to commence wireless power delivery is described nowwith reference to FIG. 3.

FIG. 3 is a block diagram illustrating example components of a wirelesscharger 300, in accordance with an embodiment. As illustrated in theexample of FIG. 3, the wireless charger 300 includes a master buscontroller (MBC) board and multiple mezzanine boards that collectivelycomprise the antenna array. The MBC includes control logic 310, anexternal power interface (I/F) 320, a communication block 330, and proxy340. The mezzanine (or antenna array boards 350) each include multipleantennas 360 a-360 n. Some or all of the components can be omitted insome embodiments. Additional components are also possible.

The control logic 310 is configured to provide control and intelligenceto the array components. The control logic 310 may comprise one or moreprocessors, FPGAs, memory units, etc., and direct and control thevarious data and power communications. The communication block 330 candirect data communications on a data carrier frequency, such as the basesignal clock for clock synchronization. The data communications can beBluetooth, Wi-Fi, ZigBee, etc. Likewise, the proxy 340 can communicatewith clients via data communications as discussed herein. The datacommunications can be Bluetooth, Wi-Fi, ZigBee, etc. The external powerinterface 320 is configured to receive external power and provide thepower to various components. In some embodiments, the external powerinterface 320 may be configured to receive a standard external 24 Voltpower supply. Alternative configurations are also possible.

An example of a system power cycle is now described. In this example,the master bus controller (MBC), which controls the charger array, firstreceives power from a power source and is activated. The MBC thenactivates the proxy antenna elements on the charger array and the proxyantenna elements enter a default “discovery” mode to identify availablewireless receiver clients within range of the charger array. When aclient is found, the antenna elements on the charger array power on,enumerate, and (optionally) calibrate.

The MBC generates beacon transmission scheduling information and powertransmission scheduling information during a scheduling process. Thescheduling process includes selection of power receiver clients. Forexample, the MBC can select power receiver clients for powertransmission and generate a Beacon Beat Schedule (BBS) cycle and a PowerSchedule (PS) for the selected wireless power receiver clients. Agraphical signaling representation of an example BBS and PS is shown anddiscussed in greater detail with reference to FIGS. 6 and 7. Asdiscussed herein, the power receiver clients can be selected based ontheir corresponding properties and/or requirements.

In some embodiments, the MBC can also identify and/or otherwise selectavailable clients that will have their status queried in the ClientQuery Table (CQT). Clients that are placed in the CQT are those on“standby”, e.g., not receiving a charge. The BBS and PS are calculatedbased on vital information about the clients such as, for example,battery status, current activity/usage, how much longer the client hasuntil it runs out of power, priority in terms of usage, etc.

The Proxy AE broadcasts the BBS to all clients. As discussed herein, theBBS indicates when each client should send a beacon. Likewise the PSindicates when and to which clients the array should send power to. Eachclient starts broadcasting its beacon and receiving power from the arrayper the BBS and PS. The Proxy can concurrently query the Client QueryTable to check the status of other available clients. A client can onlyexist in the BBS or the CQT (e.g., waitlist), but not in both. In someembodiments, a limited number of clients can be served on the BBS and PS(e.g., 32). Likewise, the CQT may also be limited to a number of clients(e.g., 32). Thus, for example, if more than 64 clients are within rangeof the charger, some of those clients would not be active in either theBBS or CQT. The information collected in the previous step continuouslyand/or periodically updates the BBS cycle and/or the PS.

FIG. 4 is a block diagram illustrating example components of a wirelesspower receiver (client), in accordance with some embodiments. Asillustrated in the example of FIG. 4, the receiver 400 includes controllogic 410, battery 420, communication block 430 and associated antenna470, power meter 440, rectifier 450, a combiner 455, beacon signalgenerator 460, beacon coding unit 462 and an associated antenna 480, andswitch 465 connecting the rectifier 450 or the beacon signal generator460 to one or more associated antennas 490 a-n. Some or all of thecomponents can be omitted in some embodiments. For example, in someembodiments, the wireless power receiver client does not include its ownantennas but instead utilizes and/or otherwise shares one or moreantennas (e.g., Wi-Fi antenna) of the wireless device in which thewireless power receiver is embedded. Additional components are alsopossible.

A combiner 455 receives and combines the received power transmissionsignals from the power transmitter in the event that the receiver 400has more than one antenna. The combiner can be any combiner or dividercircuit that is configured to achieve isolation between the output portswhile maintaining a matched condition. For example, the combiner 455 canbe a Wilkinson Power Divider circuit. The rectifier 450 receives thecombined power transmission signal from the combiner 455, if present,which is fed through the power meter 440 to the battery 420 forcharging. The power meter 440 measures the received power signalstrength and provides the control logic 410 with this measurement.

The control logic 410 also may receive the battery power level from thebattery 420 itself. The control logic 410 may also transmit/receive viathe communication block 430 a data signal on a data carrier frequency,such as the base signal clock for clock synchronization. The beaconsignal generator 460 generates the beacon signal, or calibration signal,transmits the beacon signal using either the antenna 480 or 490 afterthe beacon signal is encoded.

It may be noted that, although the battery 420 is shown for as chargedby and providing power to the receiver 400, the receiver may alsoreceive its power directly from the rectifier 450. This may be inaddition to the rectifier 450 providing charging current to the battery420, or in lieu of providing charging. Also, it may be noted that theuse of multiple antennas is one example of implementation and thestructure may be reduced to one shared antenna.

In some embodiments, a client identifier (ID) module 415 stores a clientID that can uniquely identify the power receiver client in a wirelesspower delivery environment. For example, the ID can be transmitted toone or more chargers when communication are established. In someembodiments, power receiver clients may also be able to receive andidentify other power receiver clients in a wireless power deliveryenvironment based on the client ID.

In some embodiments, a motion sensor 495 can detect motion and signalthe control logic 410 to act accordingly. For example, when a device isreceiving power at high frequencies, e.g., above 500 MHz, its locationmay become a hotspot of (incoming) radiation. Thus, when the device ison a person, e.g., embedded in a mobile device, the level of radiationmay exceed acceptable radiation levels set by the Federal CommunicationsCommission (FCC) or other medical/industrial authorities. To avoid anypotential radiation issue, the device may integrate motion detectionmechanisms such as accelerometers or equivalent mechanisms. Once thedevice detects that it is in motion, it may be assumed that it is beinghandled by a user, and would trigger a signal to the array either tostop transmitting power to it, or to lower the received power to anacceptable fraction of the power. In cases where the device is used in amoving environment like a car, train or plane, the power might only betransmitted intermittently or at a reduced level unless the device isclose to losing all available power.

II. Techniques for Reducing Exposure to Wireless Energy

Embodiments of the present disclosure describe techniques for reducinghuman exposure to wireless energy, e.g., RF energy, in wireless powerdelivery environments.

In some embodiments, techniques are discussed for increasing antennaaperture to reduce the human or user exposure to wireless energy inwireless power delivery environments. The aperture can be increased in anumber of ways. For example, the aperture can be increased by addingadditional antennas and/or by increasing the size of one or moreantennas. Accordingly, in some embodiments, techniques are described toincrease antenna aperture by using various previously unused surfaces ofa device for additional antennas. For example, antennas can be embeddedin at least a portion of the screen, e.g., glass front, of a mobiledevice.

Additional techniques for reducing human exposure to wireless energy,e.g., RF energy, in wireless power delivery environments are alsodiscussed. For example, in some embodiments, techniques are disclosedfor dynamically adjusting antenna transmission and reception radiationpatterns to reduce human or user exposure to wireless energy, e.g., RFenergy, in wireless power delivery environments. For example, an antennatransmission and reception radiation pattern can be dynamically adjustedto automatically radiate in a direction away from a user of a device toreduce SAR, e.g., RF exposure to the user.

FIG. 5 depicts a diagram illustrating example components of a wirelesspower delivery environment 500, according to some embodiments. Morespecifically, the example of FIG. 5 illustrates an example of howincreasing the aperture of a device decreases the intensity of theelectro-magnetic field or radiation pattern generated by the device ifthe amount of wireless power delivered to the device remains constant.As shown in the example of FIG. 5, the wireless power deliveryenvironment includes a wireless charger 501 and devices 502 a and 502 b.The wireless charger 501 can be a wireless charger 101 of FIG. 1although alternative configurations are possible. Likewise devices 502 aand 502 b can be wireless devices 102 of FIG. 1 although alternativeconfigurations are possible.

As shown in the example of FIG. 5, the devices 502 a and 502 b includeapertures A and B, respectively. An aperture is defined as the area,oriented perpendicular to the direction of an incoming radio wave, whichintercepts the same amount of power from that wave as is produced by theantenna which receives the wave. Typically, the intensity of theelectro-magnetic field or radiation pattern generated by a devicedecreases as the aperture increase.

As shown in the example of FIG. 5, aperture B is greater than apertureA. In wireless power delivery environments, a decrease in the intensityof the electro-magnetic field or radiation pattern generated by a deviceresults in a decrease in the intensity of the electro-magnetic fieldand, assuming the amount of wireless power delivered to the deviceremains constant, reduced RF exposure to a user of the device. Forexample, if wireless charger 501 delivers a Watt of power to both device502 a and device 502 b, the intensity of the electro-magnetic fieldgenerated around device 502 b will be less than the intensity of theelectro-magnetic field generated around device 502 a because the energyis distributed over a larger area. More specifically, the intensity ofthe electro-magnetic field generated around device 502 a isapproximately 1/A and the intensity of the electro-magnetic fieldgenerated around device 502 b is approximately 1/B.

Consequently, in some embodiments, various techniques are described forincreasing an apertures on a client device. An aperture can be increasedby increasing the physical size of the antenna or by introducingadditional antennas or replicated antennas. As discussed above withrespect to FIGS. 1-4, in some wireless power delivery environments, thewireless devices beacon the wireless charger and the wireless chargerresponds by delivering power in the direction in which the beacon wasreceived. In this manner, wireless power can be delivered to a devicesimultaneously over multiple paths by multiple antennas in a multi-pathenvironment.

In addition to distributing the electro-magnetic field generated arounddevice, increasing the aperture by using multiple antennas also providesadditional benefits. For example, when antennas are distributed over theavailable surfaces of a mobile device such as, for example, a mobilephone, one or more of the antennas may be blocked by a user of thedevice, e.g., a user holding the device might block one or more of theantennas from transmitting beacon signals to a charger. The charger, inturn, will not direct wireless power to the blocked antennas. In thismanner, a device with multiple antennas can continue to receive wirelesspower directed to only the non-blocked antennas. Because the chargerdoes not direct wireless power to the blocked antennas, the humanexposure to energy, e.g., RF exposure to the user, is reduced.

As discussed above, an aperture can be increased by increasing thephysical size of the antenna or by introducing additional antennas orreplicated antennas. Changing the size of an antenna changes thefrequency of the antenna and so, in some embodiments multiple antennas(replicated antennas) may be used so that the resonance frequency of themultiple antennas are the same or similar.

A. Dynamically Adjusting Radiation Patterns and Phased BeaconBroadcasting

FIG. 6 depicts a diagram illustrating example components of a wirelesspower reception apparatus 600, according to some embodiments. As shownin the example of FIG. 6, the wireless power reception apparatus 600includes a control system 610, one or more wireless power receivercomponents 620, and an antenna array 630. More or fewer components arepossible. The one or more wireless power receiver components maycomprise one or more components of wireless power receiver client 400 ofFIG. 4. Alternatively, in some embodiments, a wireless power receiverclient can include a wireless power reception apparatus.

In the example of FIG. 6, the antenna array 630 includes multipleadaptively-phased radio frequency antennas. As discussed in more detailbelow, each antenna can have a corresponding antenna radiation patternthat is dynamically controllable over amplitude and phase by the controlsystem 610. The radiation patterns of the multiple antennas of theantenna array 630 collectively comprise a cumulative radiation patternassociated with the wireless power reception apparatus 600.

In some embodiments, the control system 610 can be preconfigured with aset of fixed cumulative radiation patterns, e.g., one hundred or morepreconfigured amplitude and phase settings for each antenna of theantenna array 630.

FIGS. 7A-7C depict diagrams illustrating various example antennaradiation patterns of a configurable antenna array 705, according tosome embodiments. More specifically, the example of FIGS. 7A-7Cillustrate various cumulative radiation patterns 710A-C of an antennaarray 705 which includes multiple antennas. Although not shown in theexamples of FIGS. 7A-7C, the antenna array 705 can be embedded and/orotherwise included in or with a wireless power reception apparatusand/or wireless device, e.g., wireless power reception apparatus 600 ofFIG. 6. The cumulative antenna radiation patterns 710A-C are shown asexamples, other radiation patterns are possible including combinationsand/or variations thereof.

As discussed herein, antenna array 705 includes multiple antennas eachhaving an antenna radiation pattern. The cumulative radiation patterns710A-C are comprised of the radiation patterns of each of the multipleantennas of the antenna array. As will be discussed in greater detailwith respect to FIG. 8, each of the radiation patterns for the multipleantennas can be individually controlled by modifying the amplitudeand/or phase. A wireless power reception apparatus such as, for example,wireless power reception apparatus 600 of FIG. 6 can, among otherfunctions, dynamically control the cumulative antenna radiation patternof an antenna array to radiate away from a user to reduce SAR, e.g., RFexposure to the user.

FIG. 8 illustrates an example of a more detailed antenna array 805 whichincludes nine antennas 806 a-i each having a corresponding antennaradiation pattern that can be controlled over amplitude and phase. Morespecifically, the directionality and/or a type of radiation pattern canbe adjusted by modifying the amplitude and/or phase of the correspondingradiation pattern. As discussed herein, a wireless power receptionapparatus can adjust the amplitude and/or phase of each antenna todirect the cumulative radiation pattern away from a user of a device inwhich the antenna array 805 is embedded. The antenna array 805 can beantenna array 705 of FIG. 7, although alternative configurations arepossible. Antenna array 805 is shown with nine antennas shown forpurposes of illustration only. It is appreciated that antenna array 805can include any number of antennas.

As shown in equation 1, the total (or cumulative) radiation patternE_(T) is the vector summation of the radiation patterns of eachindividual antenna E_(i)(θ, ϕ):

E _(T)(θ,ϕ)=Σ_(i=1) ^(n) E _(i)(θ,ϕ)×A _(i) ×e ^(jψi),[Equation1]

where A_(i) represents the amplitude of antenna i and ψ_(i) representsthe phase of antenna i.

In some embodiments, the wireless power reception apparatus isconfigured such that the maximum radiation is directed away (outwards)from the user of the wireless device. For example, the wireless powerreception apparatus can be configured to adapt and/or otherwise modifythe radiation pattern such that it accepts more power when the antennaarray 805 is further from the head or body of the user or is oriented ina manner such that the antenna array 805 receives most power in adirection opposite the user and little or no power in other directions.

FIG. 9 depicts a diagram illustrating an example multi-path wirelesspower delivery environment 900, according to some embodiments. Themulti-path wireless power delivery environment 900 includes a useroperating a wireless device 902 including a wireless power receptionapparatus such as, for example, wireless power reception apparatus 600of FIG. 6. The charger 901 and the wireless device 902 can be charger101 and wireless device 102 of FIG. 1, respectively, althoughalternative configurations are possible.

As shown in the example of FIG. 9, the multi-path wireless powerdelivery environment 900 includes reflective objects 106 and variousabsorptive objects, e.g., users or humans, etc. In operation, thewireless device 902 broadcasts a beacon signal that is received at thecharger 901 via paths p1-p3. The charger subsequently transmits wirelesspower via paths p1-p3 to the wireless device 902. Three paths are shownin the example of FIG. 9 for simplicity, it is appreciated that anynumber of paths can be utilized.

As discussed herein, the wireless power reception apparatus of wirelessdevice 902 can be configured to adapt and/or otherwise dynamicallymodify the radiation pattern 910 such that it accepts more power whenthe antenna array (not shown) is further from the head or body of theuser or oriented in a manner such that the antenna array receives mostpower in a direction opposite the user and receives little or no powerin other directions.

Furthermore, the precise location of the RF energy pocket 911 (or powerball) and/or the angle of incidence of the RF energy received at the RFenergy pocket 911 (or power ball) can be controlled via modification tothe radiation pattern 910 to reduce and/or otherwise avoid absorption ofwireless energy, e.g., RF energy, by human flesh of user that isproximate to the wireless device 902. As discussed herein, themodifications to the radiation pattern 910 can be made via amplitudeand/or phase adjustments to one or more antennas of an antenna array ofthe wireless device 902. FIGS. 10 and 11 discusses example techniquesfor dynamically modifying radiation patterns, according to variousembodiments. Other techniques are also possible.

FIG. 10 depicts a flow diagram illustrating an example process 1000 fordynamically adjusting transmission and reception radiation patternsbased on monitored transmitted signals, e.g., beacon signals. Morespecifically, the example process 1000 illustrates a process fordetecting potential blockage or obstructions, e.g., user holding theelectronic device is such a way as to cause one or more antennas to befully or partially blocks. An electronic device having an embeddedwireless power reception apparatus, e.g., control system or controllogic of a wireless power reception apparatus control system can, amongother functions, perform the corresponding steps of example process1000. The wireless power reception apparatus can be wireless powerreception apparatus 600 of FIG. 6, although alternative configurationsare possible. Process 1000 can be a continuous process, can be commencedresponsive to movement of the device, periodically, etc., includingcombinations and/or variations thereof.

To begin, at process 1010, the electronic device selects a first antennafrom an antenna array, e.g., antenna array 630 of FIG. 6. At process1012, the electronic device transmits a beacon signal from the selectedantenna. At step 1014, the electronic device monitors and/or otherwiselistens for the transmitted signal or reflections thereof, e.g., withthe remaining antennas and/or with the transmitting antenna. At decisionprocess 1016, the electronic device determines if an obstruction ispartially or fully blocking the beacon signal. For example, in someembodiments, the electronic device can capture and process thereflection coefficient of the antenna to determine if any power isreflected. If power is reflected, the then the electronic device canconclude that an obstruction exists. In some embodiments, the reflectedpower or reflection coefficient must exceed a threshold for theelectronic device to conclude that an obstruction exists. Moreover, insome embodiments, the reflected power and/or other environmental factorscan be utilized to determine the type of obstruction.

If an obstruction exists, at step 1018, the electronic device adjuststhe amplitude and/or phase corresponding to the selected antenna and/orother antennas. For example, if an obstruction exists, the electronicdevice may determine that the obstruction is likely a human holding thedevice and decrease the amplitude corresponding to that antenna toreduce SAR, e.g., RF exposure to the user. In some embodiments, theamplitude and phases of the other antennas of the array might also beadjusted to direct the cumulative transmission and reception radiationpattern of the antenna away from the user.

FIG. 11 depicts a flow diagram illustrating an example process 1100 forcycling through the preconfigured radiation patterns, e.g., antennaarray (beacon) configurations, to dynamically identify a configurationor radiation pattern that results in lowest SAR, e.g., RF exposure tothe user, according to some embodiments. A wireless device having anembedded wireless power reception apparatus, e.g., control system orcontrol logic of a wireless power reception apparatus control systemcan, among other functions, perform the corresponding steps of exampleprocess 1100. The wireless power reception apparatus can be wirelesspower reception apparatus 600 of FIG. 6, although alternativeconfigurations are possible. The wireless power delivery system can be awireless charger or components of a wireless charger, e.g., a wirelesscharger 101 of FIG. 1 or wireless charger 300 of FIG. 3, and/or aprocessing system, e.g., control logic 310 of FIG. 3. Alternativeconfigurations are also possible.

In some embodiments, the wireless power reception apparatus, e.g.,control system or control logic of a wireless power reception apparatuscontrol system will have various preconfigured radiation patterns thatcan be cycled through or selected to select an optimal antenna (beacon)configuration. In some embodiments, the optimal antenna (beacon)configuration is the configuration in which the wireless power deliverysystem receives beacons having the strongest signal strength. In someembodiments, this configuration indicates the fewest obstructions andthus provides a configuration that results in lowest SAR, e.g., RFexposure to the user. It is appreciated that other methodologies forcycling through antenna (beacon) configurations to identify theconfiguration that results in lowest SAR are also possible.

To begin, at processes 1110A and 1110B, communication is establishedbetween the wireless device and the wireless power delivery system. Oncecommunication is established between the wireless device and thewireless power delivery system, at process 1112, the wireless deviceselects an antenna array configuration, e.g., a configuration fortransmission and reception using a particular cumulative radiationpattern. As discussed herein, in some embodiments, the configuration canindicate particular amplitudes and phases for each antenna in the array.At process 1114, the wireless device configures the antenna array basedon the selected configuration and, at process 116 transmits a beaconsignal based on the antenna configuration. At process 118, the wirelesspower delivery system receives the beacon and, at process 1119, measuresthe beacon signal strength. The wireless device might send one ormultiple beacons using the selected configuration, however, in thisexample, a signal beacon is transmitted.

At decision process 1120, the wireless device determines if theconfiguration cycle is complete. As discussed herein, there can be anynumber of predetermined configurations. If the cycle is not complete,then a new configuration is selected at process 112 and the processcontinues as discussed above. If the cycle is complete, then at process1122, the wireless device requests the configuration information, e.g.,the optimal configuration as determined by the wireless power deliverysystem. At process 1124, the wireless power delivery system receives therequest and, at process 1126, provides the wireless device with therequested configuration information. At process 1128, the wirelessdevice receives the configuration information and lastly, at process1130, configures the antenna array with the optimal array configuration.

B. Glass Front Antenna(s)

FIGS. 12A-12F depict various diagrams illustrating additional techniquesfor reducing human exposure to wireless energy, e.g., RF energy, inwireless power delivery environments utilizing glass front antennas. Thevarious components discussed with reference to FIGS. 12A-12F may be thecomponents discussed with reference to FIG. 1. For example, device 1202and charger 1201 can be wireless device 102 and charger 101 of FIG. 1,respectively. Alternative configurations are also possible.

Referring first to FIG. 12A, which depicts a diagram illustratingexample device having multiple glass screen antennas 1204.c, accordingto some embodiments. As discussed herein, in some embodiments, theantennas work in conjunction to phase the beacon in a parallelpolarization to avoid sending the beacon towards (in the direction of)the device holder. In some embodiments, a software-based antenna lobepattern management scheme is utilized which directs the wirelesspower/data back to the same antennas in the same fashion the beacon wassent. Signals emitted by the glass based antenna array do not have to bebeam forming or directional, but instead can be tailored for multipathenvironments.

FIG. 12B depicts a diagram illustrating an example arrangement ofantennas 1204.c, according to some embodiments. More specifically, FIG.12B illustrates an efficient quasicrystal antenna layout, according tosome embodiments. Other efficient arrangement of the antennas can beused to enhance the beacon broadcasting and the power/data delivery tothe device 1202. In some embodiments, the antennas 1204.c can be fractalself-similarity antennas or have various arrangements to provideenhanced communication such as quasicrystal or otherwise.

The techniques described herein are applicable with other forms orwireless power/data delivery such as magnetic resonance or electriccoupling. For example, the antennas 1204.c can be coils that work inconjunction with another surface as a charging coil ring as shown inFIG. 12C. Utilizing small, transparent or opaque coils or antenna placedabove or below a display or glass cover over intended device/system,these antennae can be utilized to receive magnetic, electric field or RFwireless power that can be harvested for use by the local electronics,battery or device.

FIG. 12D depicts a diagram illustrating an initial beacon broadcastingwhile no obstruction is present, according to some embodiments. Variousalgorithms such as, for example, genetic algorithm or annealingalgorithm can be applied to find the optimum phase for the beacon 1207.This technique can reduce or eliminate the absorbed beacon 1207 by thehuman body 1210. More importantly, this technique provides more powerfuland targeted beacon to the charger 1201 which leads to stronger andisolated power/data delivery to the wireless device 1202 comprising theantennas 1204.c. As discussed above, the isolated power delivery to thewireless device is also referred to herein as an RF energy pocket orpower ball because the wireless energy is focused by the charger overthe multiple paths in which the beacon signal is received to the preciselocation from which the beacon is transmitted.

FIG. 12E depicts a diagram illustrating an embodiment whereby at leastsome of the antennas 1204.c are blocked by an object 1209. With antennason one or both sides of a device, the beacon will be emitted from allthe antennas, but for blocked antennas, their beacon will not travel asefficiently as the open/free antennas, and the power will be returned tothe open/free antenna and not to the obscured antennas. This is alsotrue for any other algorithm that can determine the efficiency of powerdelivery to each antennae and allow the transmitter to focus its signalon the open/free antennas.

FIG. 12F depicts a diagram illustrating a general embodiment of thesystem whereby a human body (or human flesh) 1210 is present in anenvironment where a charger 1201 and a wireless device 1202 are present.More specifically, the example of FIG. 12F illustrates the beaconbroadcasting and the power delivery in the presence of a user 1210. Theclient 1203 utilizes the wireless device surface 1205 to broadcast thebeacon from the external antennas 1204.c. The beacon 1207 initiallybroadcasts in several directions as shown in FIG. 8. The beacon power isalmost negligible compared to the delivered power/data signal to thedevice 1202. The charger 1201 only corresponds to the beacon signal1207.b that lands in the charger 1201 direction. The beacon signal1207.a will not result in power/data signal delivery by the charger 1201because it's not directed towards the charger 1201. The antennas 1204.cwill utilize a beacon broadcasting algorithm to phase the broadcastedbeacon towards 1201. This technique avoids undesired directivity of thebeacon signal such as 1207.a. In addition to this, this technique willresult in a stronger phased beacon towards the charger 1201 which leadsto a stronger and more efficient power/data signal delivery withoutexposing the flesh of the user 1210 to RF power.

Several factors can affect SAR levels; one of these factors is the angleof incidence of the received RF signal on the human skin. Human skin canexhibit different RF absorption levels depending on the incidence angle.Vertical (horizontal) polarized angles of incidence lead to moreabsorption and less reflection by a dielectric material “human skin”. Onthe other hand, parallel-polarized angles of incidence lead to morereflection and less absorption by a dielectric material “human skin”which is more desirable.

In some embodiments, the techniques described herein control thepolarization of the glass screen antennas and/or the angles of incidenceto reduce and avoid absorption by the human skin. This leads to astronger broadcasted beacon signal which leads to more deliveredpower/data to the wireless device 1202. The controlled polarization ofthe glass screen antennas minimizes the absorbed power onto the humanflesh, which is highly desired. If this technique isn't utilized, humanflesh 1210 can be exposed to undesired RF signal which leads to highabsorption level rates which consequently will lead to low beacon andpower reception to the wireless device 1202.

As discussed herein, one technique that can be utilized to reduce SARlevels is to increase the aperture, e.g., number of antennas 1204.c onthe wireless device 1202 as shown in FIGS. 12A and 12B. This techniqueallows the received power signal to be distributed over the surface ofthe wireless device 1202, rather than on a specific area or individualantenna on the device.

In some embodiments, the antennas 1204.c can be oriented in differentforms to optimize the beacon received by the charger 1201 and tomaximize the power received by the device 1202. For example, the glassfront antennas can be arranged in a quasi-crystal format as shown in theexample of FIG. 12B. Alternatively or additionally, in some embodiments,the glass front antennas can be placed in a self-similarity “fractal”orientation to optimize signal transmission.

Moreover, as discussed, the antennas 1204.c can phase transmitted beaconsignals to broadcast an optimum beacon. By way of example and notlimitation, in some embodiments, an annealing algorithm or geneticalgorithm can be used to calculate the best phase for the beaconbroadcasting. This technique provides a filtered and more efficient pathfor the beacon, since a beacon exiting several antennas will naturallyhave directivity—whether on purpose or not. As discussed, the chargercan utilize the same path for wireless power/data delivery as thereceived beacon. This technique avoids absorption of the RF signal bythe human flesh by creating RF energy pockets or power balls.

The charger is configured such that if there is no beacon received fromthe client; there will be no power delivery. This technique avoidsdelivering power to undesired locations.

In case of obstruction of some of the glass screen antennas 1204.c by amaterial that may be but not limited to 1209. The non-obstructedantennas can carry the weight of the obstructed antennas. Thenon-obstructed antennas will broadcast the beacon and receive theallocated wireless power/data from the charger. This technique avoidsdelivering power to the obstructed areas of the device avoiding theabsorption of RF power signal by human flesh as shown in FIG. 12F.

Embodiments of the present disclosure describe techniques for reducingSAR levels and utilizing the screen of the wireless devices as anantenna array for broadcasting a phased beacon which leads to a morefiltered and focused wireless power/data delivery. The techniques areperformed in various ways as disclosed. Furthermore, as disclosedherein, the techniques can be performed at a charger system and/or awireless device. These techniques can be used for a variety offunctions. By way of example and not limitation, the techniquesdescribed herein can be used in various industrial, military and medicalapplications, etc.

It is appreciated that various techniques discussed herein reduce thespecial absorption rate (SAR) levels at the receiving end of the RFpower signal. In some embodiments, techniques can utilize a glass screenof the wireless device as an antenna array in different orientations.These techniques achieve at least, but not limited to, the following:delivering wireless power while maintaining exposure limits, avoidingexposing flesh to undesired RF signal levels, maintaining wireless powerdelivery efficiency, enabling devices to receive wireless power and dataregardless of the positioning of the device, allowing a device screen tobroadcast beaconing signals, and allowing the device screen to receivethe power signal from any direction without exceeding the FCC “SAR”limitations (1.6 mW/cm³).

In some embodiments, the antennas 1204.c can be placed anywhere on orwithin the wireless powered electronic device. The antennas 1204.c canbe in the form of an additional screen that can be placed on thewireless device 1202 to provide the same functionality as if its builtin the wireless device 1202 screen. The system described herein canprovide the same functionality for various types of signals other thanRF power and data signals. The system described here in can work withvarious frequencies such as 5.8 GHz. Higher frequencies lead to higherflesh absorption because of the shorter wave length and the higher powerlevels it carries.

In some embodiments, the system described herein covers any form RFpower signal delivery. The system described herein can be in differentforms or sizes. By way of example and not limiting, the charger 1201 andthe client 1203 can be in a form of an Application Specific IntegratedCircuit “ASIC” chip. The antennas 1204.c can provide functionalitywithout interfering with existing antennas and their functionality,e.g., WiFi and/or Bluetooth. The antennas 1204.c described in figuresherein can utilize to receive magnetic, electric field or RF wirelesspower than be harvested for use by the local electronics, battery ordevice. In the examples discussed herein the embodiments can include adata communication module, which can be used to coordinate events.

Additionally, in some embodiments the beacon signal, which is primarilyreferred to herein as a continuous waveform, can alternatively oradditionally take the form of a modulated signal. Furthermore, in someembodiments, wireless power delivery can be achieved between a charger1201 and a wireless device 1202 without a broadcasted beacon signal.

III. Example Systems

FIG. 13 depicts a block diagram illustrating example components of arepresentative mobile device or tablet computer 1300 with a wirelesspower receiver or client in the form of a mobile (or smart) phone ortablet computer device, according to an embodiment. Various interfacesand modules are shown with reference to FIG. 13, however, the mobiledevice or tablet computer does not require all of modules or functionsfor performing the functionality described herein. It is appreciatedthat, in many embodiments, various components are not included and/ornecessary for operation of the category controller. For example,components such as GPS radios, cellular radios, and accelerometers maynot be included in the controllers to reduce costs and/or complexity.Additionally, components such as ZigBee radios and RFID transceivers,along with antennas, can populate the Printed Circuit Board (PCB).

The wireless power receiver client can be a power receiver clients 103of FIG. 1 or wireless power reception apparatus 600 of FIG. 6, althoughalternative configurations are possible. Additionally, the wirelesspower receiver client can include one or more RF antennas for receptionof power and/or data signals from a charger, e.g., charger 101 of FIG.1.

FIG. 14 depicts a diagrammatic representation of a machine, in theexample form, of a computer system within which a set of instructions,for causing the machine to perform any one or more of the methodologiesdiscussed herein, may be executed.

In the example of FIG. 14, the computer system includes a processor,memory, non-volatile memory, and an interface device. Various commoncomponents (e.g., cache memory) are omitted for illustrative simplicity.The computer system 1400 is intended to illustrate a hardware device onwhich any of the components depicted in the example of FIGS. 1-12 (andany other components described in this specification) can beimplemented. For example, the computer system can be any radiatingobject or antenna array system. The computer system can be of anyapplicable known or convenient type. The components of the computersystem can be coupled together via a bus or through some other known orconvenient device.

The processor may be, for example, a conventional microprocessor such asan Intel Pentium microprocessor or Motorola power PC microprocessor. Oneof skill in the relevant art will recognize that the terms“machine-readable (storage) medium” or “computer-readable (storage)medium” include any type of device that is accessible by the processor.

The memory is coupled to the processor by, for example, a bus. Thememory can include, by way of example but not limitation, random accessmemory (RAM), such as dynamic RAM (DRAM) and static RAM (SRAM). Thememory can be local, remote, or distributed.

The bus also couples the processor to the non-volatile memory and driveunit. The non-volatile memory is often a magnetic floppy or hard disk, amagnetic-optical disk, an optical disk, a read-only memory (ROM), suchas a CD-ROM, EPROM, or EEPROM, a magnetic or optical card, or anotherform of storage for large amounts of data. Some of this data is oftenwritten, by a direct memory access process, into memory during executionof software in the computer 900. The non-volatile storage can be local,remote, or distributed. The non-volatile memory is optional becausesystems can be created with all applicable data available in memory. Atypical computer system will usually include at least a processor,memory, and a device (e.g., a bus) coupling the memory to the processor.

Software is typically stored in the non-volatile memory and/or the driveunit. Indeed, for large programs, it may not even be possible to storethe entire program in the memory. Nevertheless, it should be understoodthat for software to run, if necessary, it is moved to a computerreadable location appropriate for processing, and for illustrativepurposes, that location is referred to as the memory in this paper. Evenwhen software is moved to the memory for execution, the processor willtypically make use of hardware registers to store values associated withthe software, and local cache that, ideally, serves to speed upexecution. As used herein, a software program is assumed to be stored atany known or convenient location (from non-volatile storage to hardwareregisters) when the software program is referred to as “implemented in acomputer-readable medium”. A processor is considered to be “configuredto execute a program” when at least one value associated with theprogram is stored in a register readable by the processor.

The bus also couples the processor to the network interface device. Theinterface can include one or more of a modem or network interface. Itwill be appreciated that a modem or network interface can be consideredto be part of the computer system. The interface can include an analogmodem, isdn modem, cable modem, token ring interface, satellitetransmission interface (e.g. “direct PC”), or other interfaces forcoupling a computer system to other computer systems. The interface caninclude one or more input and/or output devices. The I/O devices caninclude, by way of example but not limitation, a keyboard, a mouse orother pointing device, disk drives, printers, a scanner, and other inputand/or output devices, including a display device. The display devicecan include, by way of example but not limitation, a cathode ray tube(CRT), liquid crystal display (LCD), or some other applicable known orconvenient display device. For simplicity, it is assumed thatcontrollers of any devices not depicted in the example of FIG. 9 residein the interface.

In operation, the computer system 1400 can be controlled by operatingsystem software that includes a file management system, such as a diskoperating system. One example of operating system software withassociated file management system software is the family of operatingsystems known as Windows® from Microsoft Corporation of Redmond, Wash.,and their associated file management systems. Another example ofoperating system software with its associated file management systemsoftware is the Linux operating system and its associated filemanagement system. The file management system is typically stored in thenon-volatile memory and/or drive unit and causes the processor toexecute the various acts required by the operating system to input andoutput data and to store data in the memory, including storing files onthe non-volatile memory and/or drive unit.

Some portions of the detailed description may be presented in terms ofalgorithms and symbolic representations of operations on data bitswithin a computer memory. These algorithmic descriptions andrepresentations are the means used by those skilled in the dataprocessing arts to most effectively convey the substance of their workto others skilled in the art. An algorithm is here, and generally,conceived to be a self-consistent sequence of operations leading to adesired result. The operations are those requiring physicalmanipulations of physical quantities. Usually, though not necessarily,these quantities take the form of electrical or magnetic signals capableof being stored, transferred, combined, compared, and otherwisemanipulated. It has proven convenient at times, principally for reasonsof common usage, to refer to these signals as bits, values, elements,symbols, characters, terms, numbers, or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise, as apparent from the followingdiscussion, it is appreciated that throughout the description,discussions utilizing terms such as “processing” or “computing” or“calculating” or “determining” or “displaying” or the like, refer to theaction and processes of a computer system, or similar electroniccomputing device, that manipulates and transforms data represented asphysical (electronic) quantities within the computer system's registersand memories into other data similarly represented as physicalquantities within the computer system memories or registers or othersuch information storage, transmission or display devices.

The algorithms and displays presented herein are not inherently relatedto any particular computer or other apparatus. Various general purposesystems may be used with programs in accordance with the teachingsherein, or it may prove convenient to construct more specializedapparatus to perform the methods of some embodiments. The requiredstructure for a variety of these systems will appear from thedescription below. In addition, the techniques are not described withreference to any particular programming language, and variousembodiments may thus be implemented using a variety of programminglanguages.

In alternative embodiments, the machine operates as a standalone deviceor may be connected (e.g., networked) to other machines. In a networkeddeployment, the machine may operate in the capacity of a server or aclient machine in a client-server network environment or as a peermachine in a peer-to-peer (or distributed) network environment.

The machine may be a server computer, a client computer, a personalcomputer (PC), a tablet PC, a laptop computer, a set-top box (STB), apersonal digital assistant (PDA), a cellular telephone, an iPhone, aBlackberry, a processor, a telephone, a web appliance, a network router,switch or bridge, or any machine capable of executing a set ofinstructions (sequential or otherwise) that specify actions to be takenby that machine.

While the machine-readable medium or machine-readable storage medium isshown in an exemplary embodiment to be a single medium, the term“machine-readable medium” and “machine-readable storage medium” shouldbe taken to include a single medium or multiple media (e.g., acentralized or distributed database, and/or associated caches andservers) that store the one or more sets of instructions. The term“machine-readable medium” and “machine-readable storage medium” shallalso be taken to include any medium that is capable of storing, encodingor carrying a set of instructions for execution by the machine and thatcause the machine to perform any one or more of the methodologies of thepresently disclosed technique and innovation.

In general, the routines executed to implement the embodiments of thedisclosure, may be implemented as part of an operating system or aspecific application, component, program, object, module or sequence ofinstructions referred to as “computer programs.” The computer programstypically comprise one or more instructions set at various times invarious memory and storage devices in a computer, and that, when readand executed by one or more processing units or processors in acomputer, cause the computer to perform operations to execute elementsinvolving the various aspects of the disclosure.

Moreover, while embodiments have been described in the context of fullyfunctioning computers and computer systems, those skilled in the artwill appreciate that the various embodiments are capable of beingdistributed as a program product in a variety of forms, and that thedisclosure applies equally regardless of the particular type of machineor computer-readable media used to actually effect the distribution.

Further examples of machine-readable storage media, machine-readablemedia, or computer-readable (storage) media include but are not limitedto recordable type media such as volatile and non-volatile memorydevices, floppy and other removable disks, hard disk drives, opticaldisks (e.g., Compact Disk Read-Only Memory (CD ROMS), Digital VersatileDisks, (DVDs), etc.), among others, and transmission type media such asdigital and analog communication links.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” As used herein, the terms “connected,”“coupled,” or any variant thereof, means any connection or coupling,either direct or indirect, between two or more elements; the coupling ofconnection between the elements can be physical, logical, or acombination thereof. Additionally, the words “herein,” “above,” “below,”and words of similar import, when used in this application, shall referto this application as a whole and not to any particular portions ofthis application. Where the context permits, words in the above DetailedDescription using the singular or plural number may also include theplural or singular number respectively. The word “or,” in reference to alist of two or more items, covers all of the following interpretationsof the word: any of the items in the list, all of the items in the list,and any combination of the items in the list.

The above detailed description of embodiments of the disclosure is notintended to be exhaustive or to limit the teachings to the precise formdisclosed above. While specific embodiments of, and examples for, thedisclosure are described above for illustrative purposes, variousequivalent modifications are possible within the scope of thedisclosure, as those skilled in the relevant art will recognize. Forexample, while processes or blocks are presented in a given order,alternative embodiments may perform routines having steps, or employsystems having blocks, in a different order, and some processes orblocks may be deleted, moved, added, subdivided, combined, and/ormodified to provide alternative or subcombinations. Each of theseprocesses or blocks may be implemented in a variety of different ways.Also, while processes or blocks are, at times, shown as being performedin a series, these processes or blocks may instead be performed inparallel, or may be performed at different times. Further, any specificnumbers noted herein are only examples: alternative implementations mayemploy differing values or ranges.

The teachings of the disclosure provided herein can be applied to othersystems, not necessarily the system described above. The elements andacts of the various embodiments described above can be combined toprovide further embodiments.

Any patents and applications and other references noted above, includingany that may be listed in accompanying filing papers, are incorporatedherein by reference. Aspects of the disclosure can be modified, ifnecessary, to employ the systems, functions, and concepts of the variousreferences described above to provide yet further embodiments of thedisclosure.

These and other changes can be made to the disclosure in light of theabove Detailed Description. While the above description describescertain embodiments of the disclosure, and describes the best modecontemplated, no matter how detailed the above appears in text, theteachings can be practiced in many ways. Details of the system may varyconsiderably in its implementation details, while still beingencompassed by the subject matter disclosed herein. As noted above,particular terminology used when describing certain features or aspectsof the disclosure should not be taken to imply that the terminology isbeing redefined herein to be restricted to any specific characteristics,features, or aspects of the disclosure with which that terminology isassociated. In general, the terms used in the following claims shouldnot be construed to limit the disclosure to the specific embodimentsdisclosed in the specification, unless the above Detailed Descriptionsection explicitly defines such terms. Accordingly, the actual scope ofthe disclosure encompasses not only the disclosed embodiments, but alsoall equivalent ways of practicing or implementing the disclosure underthe claims.

While certain aspects of the disclosure are presented below in certainclaim forms, the inventors contemplate the various aspects of thedisclosure in any number of claim forms. For example, while only oneaspect of the disclosure is recited as a means-plus-function claim under35 U.S.C. § 112, ¶6, other aspects may likewise be embodied as ameans-plus-function claim, or in other forms, such as being embodied ina computer-readable medium. (Any claims intended to be treated under 35U.S.C. § 112, ¶6 will begin with the words “means for”.) Accordingly,the applicant reserves the right to add additional claims after filingthe application to pursue such additional claim forms for other aspectsof the disclosure.

The detailed description provided herein may be applied to othersystems, not necessarily only the system described above. The elementsand acts of the various examples described above can be combined toprovide further implementations of the invention. Some alternativeimplementations of the invention may include not only additionalelements to those implementations noted above, but also may includefewer elements. These and other changes can be made to the invention inlight of the above Detailed Description. While the above descriptiondefines certain examples of the invention, and describes the best modecontemplated, no matter how detailed the above appears in text, theinvention can be practiced in many ways. Details of the system may varyconsiderably in its specific implementation, while still beingencompassed by the invention disclosed herein. As noted above,particular terminology used when describing certain features or aspectsof the invention should not be taken to imply that the terminology isbeing redefined herein to be restricted to any specific characteristics,features, or aspects of the invention with which that terminology isassociated. In general, the terms used in the following claims shouldnot be construed to limit the invention to the specific examplesdisclosed in the specification, unless the above Detailed Descriptionsection explicitly defines such terms. Accordingly, the actual scope ofthe invention encompasses not only the disclosed examples, but also allequivalent ways of practicing or implementing the invention.

What is claimed is:
 1. An apparatus comprising: one or more computerreadable storage media storing program instructions that, when executedby one or more processing systems associated with a wireless powerreception apparatus, cause the one or more processing systems to: directone or more of multiple antennas of an electronic device to dynamicallyadjust a cumulative radiation pattern for reducing wireless energyexposure to a user of the electronic device, wherein the wireless powerreception apparatus is configured to wirelessly receive power from awireless power delivery system in a wireless power delivery environmentand provide the power to the electronic device or an energy storageapparatus adapted to provide the power to the electronic device.
 2. Theapparatus of claim 1, further comprising: the multiple antennas, whereinthe multiple antennas have corresponding radiation patterns that areadjustable over amplitude and phase by the one or more processingsystems, and wherein the radiation patterns collectively comprise thecumulative radiation pattern.
 3. The apparatus of claim 2, wherein theprogram instructions, when executed by the one or more processingsystems, cause the one or more processing systems to: detect one or morefull or partial blockages of the radiation patterns corresponding to themultiple antennas.
 4. The apparatus of claim 3, wherein the cumulativeradiation pattern is adjusted based on the one or more full or partialblockages of the radiation patterns.
 5. The apparatus of claim 1,wherein the program instructions, when executed by the one or moreprocessing systems, cause the one or more processing systems to: detectan orientation of the cumulative radiation pattern relative to the userof the electronic device.
 6. The apparatus of claim 3, wherein thecumulative radiation pattern is adjusted based on the orientation of thecumulative radiation pattern relative to the user of the electronicdevice.
 7. The apparatus of claim 1, wherein to dynamically adjust thecumulative radiation pattern, the program instructions, when executed bythe one or more processing systems, cause the one or more processingsystems to: adjust a direction or intensity of a beacon signaltransmitted by the multiple antennas.
 8. The apparatus of claim 1,wherein to dynamically adjust the cumulative radiation pattern, theprogram instructions, when executed by the one or more processingsystems, cause the one or more processing systems to: adjust an angle ofincidence of the power received from the wireless power delivery system.9. The apparatus of claim 1, wherein to dynamically adjust thecumulative radiation pattern, the program instructions, when executed bythe one or more processing systems, cause the one or more processingsystems to: cycle through a set of fixed cumulative radiation patternsto identify an antenna configuration that results in the lowest wirelessenergy exposure to the user of the electronic device.
 10. The apparatusof claim 1, wherein to dynamically adjust the cumulative radiationpattern, the program instructions, when executed by the one or moreprocessing systems, cause the one or more processing systems to: adjustthe cumulative radiation pattern in a direction away from the user ofthe electronic device.
 11. A wireless power reception apparatuscomprising: a control system adapted to direct multiple antennas of anelectronic device to dynamically adjust a cumulative radiationcumulative radiation pattern for reducing wireless energy exposure to auser of the electronic device, wherein the wireless power receptionapparatus is configured to wirelessly receive power from a wirelesspower delivery system in a wireless power delivery environment andprovide the power to the electronic device or an energy storageapparatus adapted to provide the power to the electronic device.
 12. Thewireless power reception apparatus of claim 11, further comprising: themultiple antennas, wherein the multiple antennas have correspondingradiation patterns that are adjustable over amplitude and phase by thecontrol system, and wherein the radiation patterns collectively comprisethe cumulative radiation pattern.
 13. The wireless power receptionapparatus of claim 12, wherein the control system is further adapted to:detect one or more full or partial blockages of the radiation patternscorresponding to the multiple antennas, wherein the cumulative radiationpattern is adjusted based on the one or more full or partial blockages.14. The wireless power reception apparatus of claim 11, wherein thecontrol system is further configured to: detect an orientation of thecumulative radiation pattern relative to the user of the electronicdevice, and wherein the cumulative radiation pattern is adjusted basedon the orientation of the cumulative radiation pattern relative to theuser of the electronic device.
 15. The wireless power receptionapparatus of claim 11, wherein the control system is further configuredto: adjust a direction or intensity of a beacon signal transmitted bythe multiple antennas.
 16. The wireless power reception apparatus ofclaim 11, wherein to dynamically adjust the cumulative radiationpattern, the control system is adapted to: adjust an angle of incidenceof the wireless power received from the wireless power delivery system.17. The wireless power reception apparatus of claim 11, wherein todynamically adjust the cumulative radiation pattern, the control systemis adapted to: cycle through a set of fixed cumulative radiationpatterns to identify an antenna configuration that results in the lowestwireless energy exposure to the user of the electronic device.
 18. Thewireless power reception apparatus of claim 11, wherein to dynamicallyadjust the cumulative radiation pattern, the control system is adaptedto: adjust the cumulative radiation pattern in a direction away from theuser of the electronic device.
 19. An electronic device comprising:electronic components including one or more processors; multipleantennas disposed on or within the electronic device; and a controlsystem adapted to direct the multiple antennas to dynamically adjust acumulative radiation cumulative radiation pattern for reducing wirelessenergy exposure to a user of the electronic device, wherein the wirelesspower reception apparatus is configured to wirelessly receive power froma wireless power delivery system in a wireless power deliveryenvironment and provide the power to the electronic device or an energystorage apparatus adapted to provide the power to the electronic device.20. The electronic device of claim 19, wherein the control system isfurther adapted to: detect one or more full or partial blockages ofradiation patterns associated with the multiple antennas, wherein eachof the multiple antennas have a corresponding radiation pattern that isadjustable over amplitude and phase by the control system, wherein theradiation patterns collectively comprise the cumulative radiationpattern, and wherein the cumulative radiation pattern is adjusted basedon the one or more full or partial blockages.